I have always got the instructor to add his number and signature in my logbook, otherwise how do you work out/prove you are current?

A line in the logbook with the Instructor's name in the 'Captain' column and 'PUT' in "Holder's Operating Capacity" provides the same level of proof as all your PIC lines do.

I said 'his number' as well

I know you did; I'm simply pointing out that your PIC lines have no "proof" in them other than your formal statement that "all entries are correct" - which covers the Instructor entry as well.

AMC.FC050 requires all instruction time to be certified by the Instructor.

What does "A summary... may be logged" actually mean?

You log hours, not a "summary". I find that AMC confusing.

The point is that the flight with an instructor is required for currency, and to be valid, must be signed by the instructor.

But that refers to an applicant for a licence or rating which is not relevant here.

I'm amazed that the question: "Have you flown twelve hours in the last 2 years, one of them with an instructor?" Can cause so much difficulty and confusion.

MaxR

Keeping your licence current, and what to do if you don’t meet the requirements

The privileges of your licence will only remain valid if you have completed, in the last 24 months, as pilot of an aeroplane or TMG:

1. At least 12 hours flight time as PIC, including 12 take-offs and landings; and
2. Refresher training of at least 1 hour of total flight time with an instructor.

With respect, no-one has yet properly addressed the issue of whether the hour can be done with a foreign (European) instructor. Anyone?

I think it's fair to say they are talking about someone with any EASA FI certificate since you can fly any EASA registered airplane in any EASA state.

Sorry, what was it I said that made you think I didn't already know that?

A quick question for an expert please.

My LAPL has three pages titled 'XII - Certificate of Revalidation' similar to those in my UK PPL which I get signed every two years when I complete my bi-ennial check.

Given that the LAPL has a 24 month rolling validity, what are the Certificates of Revalidation for? When are they filled out? I understand that the Bi-ennial is still entered in the logbook.

Do I still need an examiner's or instructor's signature for the license to remain valid?

Can anyone help me to understand how I stay legal?

There is no bienial check; you simply do a training flight or series of flights with an Instructor who signs your log book.
The Certificate pages are in your licence because the CAA only have one format for printing licences and in the case of the LAPL are totally surperfluous.
So long as your log books shows your currency and the 1 hour training within the past 24 months you are legal. Any EASA FI or CRI can do that. There is no expirey date or validity shown in the licence.

The way I read that, the revalidation pages are for when you need to have your licence validated again, because you failed to keep it valid.

But NOT in the case of a LAPL, they remain BLANK. The licence is valid for the lifetime of the holder.

One option for regaining LAPL recency is by compliance with FCL.140.A(b)(1), which means by the completion of a Proficiency Check with an Examiner.

It would not be unreasonable for this to be entered in the LAPL Certificate of Revalidation, rather than in a pilots flying log book.

However, the requirement is not totally clear.